Signaling system for single-track roads



S. N. WIGHT. SIGNALING SYSTEM FOR SINGLE TRACK ROADS. ArPLICATlON FILEDmac :0. 1920. 1,427,882. Pat n dSepti 5, 1922.

3 SHEETS--SHEET I S. N. WIGHT.

SIGNALING SYSTEM FOR SINGLE TRACK ROADS.

ArPLlCATlON FILED DEC, 10.1920.

1 27,882, r PatentedSept. 5, 1922.

3 SHEETS SHEET 2' Fl 6.3.

S. N. WIGHT.

SIGNALING SYSTEM FOR SINGLE TRACK ROADS.

ArPLICATION FILED mac. I0. I920.

1,427,8 3 PatentedSept. 5, 19 22 3 SHEETS-SHEET 3.

block system.

Patented Sept. 5, 1922.

iSEDGrWICK N. WIGHT, OE=BOCHESTER,NEWiYORK, 'ASSIGNOEYTOQGENERAL RAILWAYr -rries. I

SIGNAL COMPANY, OF GATES, NEW YOBK,.:A CORl OR-ATION OENEW 'YORK.

srsnurirns SYSTEM more .sms E-mnAoK nouns.

Application fi1ed..Dece1nber 10,1920. Serial No. 429,702.

"T 0 all 107mm it may concern:

Y Be it a known that I, Snnowron N. WIGHT, a citizeno f the UnitedStates, residing at Rochester, in the county of Monroe and State of NewYork, have invented certain new and useful Improvements in SignalingSystems for Single-Track Roads, of which the following is aspecification.

.Thisinvention relates .to:.block signal/systems for single trackrailroads, ofthe type commonly known as. an absolute-permissive- In one.type oi an A. P613. system, such .as described, for example, .ininyprior Patent .No. 1,294,736, dated .Feb. 18,1919, if two opposing trainshappen to pass simultaneously the starting signals at the opposite endsof thestretchof single track between the passing sidings, a lock-upcondition occurs which leaves all of the signals of that stretch oftrack'at stop, regardless of 3 train movement. Such a condition willonly,

occur when there isan unauthorizing train .movement, or other abnormalcondition, but

since the result is to. compeliall trains to flag through that singletrack block until the lock-up condition is corrected, additionalItacility ottrain movement would be provided, it the systemdsso'eonstructed and arranged that this lock-up condition willbeautomatically removed when the trainat fault backs out of the singletrack block.

One of theprincipal ob ects of thepres-s ent inventionis to provide asystem of the' type described in which the signals may assume theirregular working condition after a simultaneous movement of two opposingtrains past/the starting signals, as soon as one of these trains backsout. of the single track block.

Other specific objects andadvantages of the invention will appear as thedescription otthe inventionprogresses and '.tl1e novel features will bepointed out infthe appended.

claims. I k V For the purpose of explaining theneed and utility of thepresent invention there 1s shown in thetaccompanying drawingspart- .olthe complete A.

P. .13. system shown in detail and fully described inmy pr1orpatentabovementioned. with the present invention incorporated therew1th;but1tshould be understood that the invention is vnotllim .ited to thisspecific system andmay be .ein

bodied in other specific formsin connection with otheri similar A. PfB,systemsby mak .ing the appropriate detail changes.

In the accompanying drawings,

Fig. 1 shows in a diagrammatic and simplified wa one arrangement ofsignals "for an AP. .system; i I

Fig. 2 shows'in a simplified manner a po r- 'tlon of slngle trackadjacent to one siding, togethenwith the signals, relays,.andcontrolling circuits associated .with this portion of track, andconstituting that part or the "complete system shown in my prior patentwith which the device and circuits embodyingthe present inventionareasslociated;

ig. 3 isadiagrannnatic .view similar to Fig; 2, with some relays andcircuits omitted, which {shows one form of the invention and Figs. 1,5and Gare'diagrammatie views similar to Fig. 3, whichillustrate modifiedforms of It-he invention.

Referring to'Fig. 1,.there is illustrated a stretch Tot single track 1(indicated by the singleheavyline) and a passing. si'cling S andS ateach=end ofthis stretch. The

stretch is dividediin 'the usual mannerinto a number o'f'itrac-ksections .A, .B, C' etc. Signals 5, 6, "7 and 8 govern ,tra'flic fromright to left, I in the dl'rectlon .md ca-ted by the arrow Y; a.1'1clsig1ia ls 9,'10, 11 and12 govern.trailic' trom'l'eft to right, inthedirection indicated by the arrow The sig nals 8 "and 9 atnthe endsof'the stretchare I provided with square ended'blades and marker l ghtssoas to [be 'distinguishalfle from the other intermediate:signals, saidsignals Sand 9' being commonlyknownias the starting or absolute signals.

Referring now to (Fig. '2, there is illustrated a po'rtioirot'the systembetween the signals 9, and 10. i The track rails 1 and 2 of thetrackarexdivided by insulated joints 3 into electrically isolated tracksections A,

.B, C and D. Each of thesetraok sections is provided with a trackbattery 4 and a track relay'in the usual. waypthe traclrrelays'be- ,ingdesignated 13 16. "Associated with the ciated with one signal'9 willsuflice .to give a clear understanding of the present invention.

The signal 9 is controlled by a line relay 17, sothat when this relay isenergized, the

each signal, one terminal of this battery being connected to a commonwire extending along the track. Some of the circuits are local and areindicated as terminating at B and N. Other circuits extend from onesignal location to another and are indicated by notations B and K.

The energizing circuit for the line relay 17 may be traced as follows:Commencing at the common wire K, relay 17, wire 25, front contact 26 oftrack relay 14, wire 27, front contact 28 of track relay 15, wire 29,back contact 30 of stick relay 22 of the opposing signal ('3, wire 31,and thence either through front contact 32 of the line relay 18 ofsignal 10, or through the front contact 33 of the stick relay 21 of saidsignal 10, to B,

Thus, it will'be observed that the line relay 17 is deenergized, and thesignal 9 put to stop in case :(1) either of the track sections B or C isoccupied; (2) the stick relay of the opposing signal 6 is picked up; and(3) if the line relay 18 of the next signal 10 in advance isdeenergized, and the corresponding stick relay 21 is not energized atthat time. The line relay 18 of signal 10 is in turn controlled in asimilar way by a line relay at signal 11 (see Fig. 1), and the latterline relay in turn controlled by the track circuits ii and G, with theresult that a train entering the stretch of track on to the tracksection G causes successive dropping of the line relays of signals 11,

10 and 9 and puts these signals to stop. The

'stick relays associated with these signals are A train, traveling fromleft to right, when it enters the track section B, closes this pick-upcircuit for the stick relay 20, because back contact 36 of the trackrelay let is closed, and the circuit controller 88 of the signal 9 isalso closed, since the signal 9 is in the proceed position, otherwisethe train would not enter this track section, A train traveling in theopposite direction, however, puts the signal 9 to stop before it gets onthe track section B, so that the pickup circuit for the stick relay 20is broken at the circuit controller 38. In this way the stick relay 20is energized when a train passes the signal 9 in the direction in whichthis signal governs traflic, but is not picked up by a train travelingin the opposite direction.

When the stick relay 20 has been energized, it is maintained energizedby a stick circuit, which may be traced as follows: Con'imencing at thenegative battery N relay 20, wires 3 1 and 39, front contact 40 of said.stick relay 20, wire 41, and back con tact 23 of the line relay 1?, toB. This stick circuit is maintained so long as the line relay 1'7 isdeenergized,

Assuming a train, traveling from left to right (in the directionindicated by the arrow X), passes the signal. 9 and enters track sectionB, the signal 9 is then put to stop, on account of the opening of thecircuit for the line relay 17 at the front contact 26 of the track relay1%. In a similar way the line relay 19 is deenergized when track relaylst drops, and puts the signals 6 to stop. The dropping of line relay 19in turn drops the line relay of signal 7, putting that signal to stop,and the line relay of signal 7 in turn drops the line relay of signal 8,putting this signal to stop, thereby blocking all opposing trainmovements. As the train in question passes from the track section B intothe track section 0, conditions remain unchanged, lVhen the train passessignal 10, it causes dropping of line relay 18, so as to put the signal10 to stop, and also makes another break in the line circuit for linerelay 1'? at front contact 82. The stick relay 21, however, is picked upin the same way as above explained in connection with stick relay 20, sothat when the train leaves the track sections B and C, the line relay 17may again pick up and cause the signal 9 to clear. It is noted at thispoint that the control circuits and devices for governing the diagonalor caution position of the signals has not been shown in the circuitarrangements, in order to avoid unnecessary complication, this cautioncontrol being obtained in accordance with any of the wellknown systems,such as shown in my prior patent above mentioned. When the train enterstrack section D, it opens another break in the line circuit for signal7, When shown in Fig. 3. IuFig. 4:, the stick circuit for the relay 20includes back contacts 47 and 48 of the track relays 1e and 15, inmultiple, so that so long as either of the track sections B or C isoccupied, said stick circuit is maintained. This arrangement operates inthe same way as originally explained in connection with Fig. 3.

Fig. 5 illustrates still another way of antomatically restoring thesystem to normal after the lock-up condition has occurred; According tothis modification, provision is made for knocking down the stick relay,as 20, associated withone or both of the starting signals, whena trainthat has entered the stretch of single track backs out. Referring toFig. 5, the pickup and stick circuits for the stick relay 20 are thesame as shown in Fig. 2, except that the negative battery N, is takenthrough a back contact 4:9 of an auxiliary relay WV, so that when thisrelay WV is picked up, the relay 20 is deenergized.

The energizing circuit for relay WV may be traced commencing at N, relay'VV, wire 50, back contact 51 of track relay 13,'wire 52, front contact53 of track relay 14, wire 5% and circuit controller 55 closed with thesignal 9 in the horizontal or stop position.

This control of the auxiliary relay N is such that said relay is notenergized when a train travels from left to right in the directionindicated by the arrow X, but is energized when a train, starting inthis direction, reverses its direction of movement and backs up intotrack section A out of track sect-ion B. When a train traveling fromleft to right enters track section A, the circuit for relay WV is closedat the back contact 51, but is open at the circuit controller 55 (itbeing assumed that there is no train in the stretch.) As this trainproceeds it opens said circuit for relay W at the front contact 53before said circuit is closed at the circuit controller 55, and when thetrain has proceeded far enough to allow track relay ll to pick up andclose its front contact 53. the rear end of said train has passed off ofthe track section A, with the result that said circuit for relay is nowbroken at back contact 51. Thus, the relay lV is not energized by anormal train movement from left to right, this train movement being theone picked up. Consequently, relay W does not interfere with the regularoperation'of the system. Suppose, however, the train, after getting intotrack section B, backs up. Circuit controller 55 is closed, having beenclosed when the train entered track section B. Back contact 51 isclosed, because the train is now on track section A. Consequently,during the interval after the closing of the front contact 53 andopening of the circuit controller 55, the energized circuit for relay WVis established, and the stick relay 20 is deenergized. If desired, thisinterval may be increased by making the'circuitv controller 55 so thatit makes contact during a portion of the movement of the signal 9 upwardfrom its stop position.

Referring to the operation of the modification shown in Fig. 5, if twotrains should happen to enter opposite ends of the stretch at about thesame time, the stick relays associated with the signals 9 and 8 wouldpick up, and the lock-up conditionhereinbefore explained would result.These two trains could not proceed according to signal indie cations,and even if they attempted to flag through, one would have to back upuntil behind its corresponding starting signal 8 or 9. Thisfback-upmovement would pickupthe corresponding auxiliary relay V and drop thecorresponding stick relay, as above explained; and consequently thelock-up condition would be broken. 1

It will be evident that the stick relay, as 20, at the starting signals8 or 9, may be deenergized or knocked down by a back-up movement of atrain, by specific arrangements of circuits and devices other than theone shown in Fig. 5. For example. in one arrangement shown in Fig. 6,the stick relay 20, is knocked down by a back-up movement as described,by shunting out said relay through a suitable resistance 56 to avoidshort circuiting the battery. The same back contact 51 of track relay13, the front contact53 of track relay 14, and circuit controller 55 ofsignal 3 are employed in this modified arrangement shown in Fig. 6, asin the arrangement, shown in Fig. 5, the circuit including the shuntingresistance 56 being closed under the same conditions of train movementpreviously explained. v

Fromthe foregoing it will be observed that I have provided improvedarrangements of circuits and devices, by means of whichtrain movement isfacilitated in case two trains should happen by accident to enteropposite ends of the stretch of. single track at approximately the sameinstant, while at the same time retaining the safety feature of checkingthe deenergization of the several stick relays; and while I have shownmy invention incorporated with a specific type of anabsolLite-permissive block system the same principles may be applied toother types of systems. I desire to have it understood, therefore, thatthe specific arrangements of circuits and devices shown and describedare merely illustrative of the invention, and do not exhaust the variousphysical embodimentsof the idea of means constituting the invention.

hat I claim asnew and desire to secure by Letters Patent of the UnitedStates, is

1. In signal system for single track railroads having two sets ofsignals at intervals along a stretch of single track between two nalincluding, a back contact of the stick relay associated with the nextopposing sig nal', a stick circuit for each relay controlled by thelinecircuit of the corresponding sigs nal,and means associated with eachof the 5 starting signals at the ends of said stretch for causingdeenergizatlon oi: the corresponding stick relay when a train moves bythat signal oppositeto the direction of trafiic governed thereby. I

2. In a signaling system of the type specified in claim 1, thecombination witlr the starting signal at the end of the stretch and thestick relay associated therewith, of means for interrupting the stickcircuit of said relay when a train passing a signal in the direction oftraffic governed thereby backs up into the track section in the rearthereof.

3. In a signaling system of the type specified in claim 1, thecombination with each of the starting signals at the ends of the stretchof single track and the stick relays associated therewith, of meansdependent upon the direction of movement of trains pasts'aid signals forgoverning the stick circuit of the corresponding stick relay.

4:. In a signal system of the type specified in claim 1, the combinationwith each of the starting signals at the ends of the stretch of singletrack and the stick relay associated therewith, of means including frontand back contacts on the track relays of the track sections adjacent toeach signal for governing the stick circuit of the corresponding stickrelay.

5. In a signal system of the type specified in claim 1, the combinationwith thestarting signal at one end of the stretch of single track andthe stick relay associated there with, of a slow acting circuitcontroller governed by the line circuit of said signal and opened orclosed when said linecircuit is energized and deenergized respectively,and means for controlling the e'nergization o'l said stick relay, saidmeans comprising a.

circuit including said circuit controller and front and back contactsrespectively of the track relays of the track sections next in ad vanceand in the rear of said signal.

6. In a signal system for single track railroads having two sets ofsignals governing trafiic in opposite directions over a stretch ofsingle track between two passing sidings, a directionally controlleddevice associated with said signals and responsive to the di rection ofmovement of trains, said device of each signal acting when active tohold the next opposing signal at stop, and means associated with thestarting signals at the ends ofsaidstretch for automatically restoringthe corresponding device to thenormal condition when a train havingentered. the stretch from-that end backs up out of the track sections inadvance of the corresponding: starting signal, k,

7. Ina signal systematorsingle track railroads having two sets ofsignals governing traflic in opposite directions over a stretch ofsingle trackbetween two passing sidings, aline circuittor each signalcontrolled by the track relay oft-he track sections protected thereby,the linecircuit ofeach signal being controlled by the line circuit ofthe signal next inadvan'ce which governs trafiic in the samedirection,,-a' directionally con trolled deviceqassociated with eachsignal and'change'd to an act-ivecondition byatrain moving in the Idirection. of} trafiic' governed by that signal, said device of'eachsignal acting when active to hold the next opposing signal at stop, andmeans associated with the starting signals at the end of the stretch formaintaining the corresponding device active when once rendered active solong as a train causing such change occupies the track sec tionprotected by that signal, said means automatically restoring said deviceto the normal condition when such train reverses its direction ofmovement and backs out of the track sections protected by thecorretrain; occupies a certain portion of the stretch, and automaticmeans for independently restoring said device-to the normal conditionwhen such train reverses its direction of movement and backs out of saidcertain portion of the stretch.

9.. Ina signal system for single track railroads having a stretch ofsingle track between two passing sidings, the combination with signalsat opposite ends of the stretch and governing train movement into thestretch, of a normally deenergized stick relay associated with eachsignal and automatically energized by a train moving in the directionsof traflic governed thereby, and means, for causing deenergization ofeach stick relay when a trainhavingpassed the corresponding signal inthe direction of traflic governed thereby backs up in the rear of thatsignal.

10. In an absolute permissive-bloek signal system for single trackrailroads of the type described, the combination with the startingsignal at the end of the stretch of single track, a normally deenergizedstick relay associated withsaid signal, pick-up and stick circuits forsaid relay, and means governing both the pick-up and stick circuits ofsaid relay, comprising front and back contacts of track relays oftracksections adjacent to and on opposite sides of the signal.

11. In an absolutepermissive-block signal system for single trackrailroads of the type described, the combination with the startingsignal at the entrace to the stretch of single track, a stick relay,pick-up and stick circuits for said relay, and means governing both thepick-up and stick circuits of said relay, comprising a normally openedcircuit controller closed when the track circuits next in advance of thesignal are occupied.

12. In a signal system for single track railroads having a stretch ofsingle track between two passing sidings, a starting signal at one endof the stretch, a normally closed circuit controller operated by thesignal and opened during movement thereof to its biased stop position, astick relay, a pick-up circuit for the relay including said circuitcont-roller and a back contact of the track relay next in advance ofsaid signal, a line circuit governed by a plurality of track circuits inadvance of the signal, a stick circuit for said relay closed at onepoint when said line circuit is deenergized, and means comprising frontand back contacts of track relays adjacent to and on opposite sides 01said signal. for governing the continuity of both the pickup and stickcircuits of said relay.

In testimony whereof I afiix my signature.

SEDGWIOK n. wrsnr

